Pump construction



Feb. 16, 1965 H. J. SADLER ETAL PUMP CONSTRUCTION 2 Sheets-Sheet 1 FiledNov. 1, 1965 lllll Ill:

INVENTORS. HARRY J. SADLEF? ERNES T E. COOK ATTORNEYS Feb. 1965 H. J.SADLER ETAL PUMP CONSTRUCTION 2 Sheets-Sheet 2 Filed Nov. 1, 1963INVENTORS. HARRY J SADL ER EgNEST E. COOK ATTOPNE YS United StatesPatent Ofi'ice 7 means Patented Feb. 16, 1965 3,16%,485 PUT/llSGNSTRUCHGN Harry J. Sadler, Minneapolis, and Ernest E. Cook, {IconRapids, Minn, assignors to Hypro Engineering, Inc., Minneapolis, Minn acorporation of Minnesota Filed Nov. 1, 1963, Ser. No. 329,792 4 Claims.(Cl. 103-4) Our invention relates generally to rotary fluid pumps andmore particularly to fluid pumps of this character which are ofrelatively low-capacity and small of size.

Still more specifically, our invention relates to improvements in rotorsfor pumps of the type above described whereby the capacity of pumpsincorporating same is materially increased.

Still more specifically, our invention relates to fluid pumps of thetype utilizing flexible resilient rubber-like vane impeller elements. Itis well known that pumps of this character have good self-primingproperties, are able to eh'rciently move abrasive materials and arerelatively quiet. On the other hand, because or" the well-known tendencyof the several vanes of such rotors to flex rearwardly and radiallyinwardly responsive to similar forced movements of adjacent vanes(caused by engagement with the cylindrical side walls of the pump asthey approach the high pressure side of the pump), such pumps haverelatively low pressure limits. Roller pumps, on the other hand, areknown to achieve higher pressures and to have lower starting torque.

The primary object of our invention is the provision of a pump having arotor which incorporates the benefits of both the flexible vane androller-type pumps.

More specifically, it is the object of our invention to provide a rotorwhich has a plurality of circumferentially spaced flexible resilientrubber-like pocket-forming impeller elements, at least one of saidpockets having mounted and guided therein for limited reciprocalmovements generally radially or" said rotor a relatively rigid impellerelement which is in constant substantial engagement with the cylindricalwall of the casing during rotation of the rotor, and which tends tofunction as a check valve whereby to break up any tendency of thesucceeding flexible resilient impeller elements to flatten out andbypass fluid under progressively higher pressures.

A still further object of our invention is the provision of a device ofthe class above described which incorporates a minimum of working partsand is relatively inexpensive to produce.

A further object of our invention is the provision or" a pump of theclass described which, while retaining the good self-priming features ofa conventional rubber impellet-type pump, is capable of operating underpressures far in excess of that achievable through the mediurn of suchpumps.

A still further object of our invention is the provision of a pump whichis considerably quieter than conventional roller-type pumps.

A still further object of our invention is the provision of a pump ofthe class immediately above described which is capable of pumpingabrasive materials With greater efliciency than a roller-type pump.

The above and still further objects of our invention will becomeapparent from the following detailed specification, appended claims andattached drawings.

Referring to the drawings, wherein like characters indicate like partsthroughout the several views:

FIG. 1 is a View in end elevation of a pump constructed in accordancewith our invention;

PEG. 2 is a view in side elevation of the structure of FIG. 1;

FIG. 3 is a view in vertical section as seen from the line 3-3 of FIG. 2on an enlarged scale, some parts being broken away;

FIG. 4 is a vertical section taken on the line 4-4 of FIG. 1 on anenlarged scale;

FIG. 5 is a view in end elevation of the rotor of our pump, removed fromthe drive shaft;

FIG. 6 is a view in side elevation of our rotor, mounted on the shaft,portions of which are broken away and shown in section;

FIG. 7 is a view in section taken on the line 7-7 of FIG. 5 and FIG. 8is an exploded view in of our novel rotor.

Referring with greater particularity to the drawings, the housing of ournovel pump, identified in its entirety by the numeral it defines achamber ll having spaced parallel end walls 12, a cylindrical side wall13 and diametrically opposed inlet and outlet ports 14 and 15respectively which communicate with said chamber 11. In conventionalmanner, the housing 10 is provided with a removable end plate 16.Journalled for rotation in bearing bosses 17, in radially offsetrelation to the axis of the cylindrical chamber 11, is a shaft 18 havingmounted fast thereon for common rotation within the chamber 11 a rotor19. V

Rotor 19 comprises a diametrically enlarged hub 29, which is dividedinto two parts, namely, a relatively rigid tubular core element 21 and arelatively flexible radially outer portion 22. Preferably the coreelement 21 is formed from suitable steel, whereas the outer portion 22is formed from rubber-like material capable of being bonded to the coreelement 21. Core element 2i, on the other hand, is secured fast to theshaft 18 in any suitable manner.

The rotor 19 also includes a plurality of circumferentially spacedflexible resilient vane-like impeller elements 23 which are, preferablyand as shown, formed integrally with the radially outer portion 22of'the rotor 1?. As shown, the normal radial dimensions of the vanes 23are such that their radial outer limits 23a are in constant sweepingengagement with the cylindrical side wall 13 of the chamber 11 duringrotation thereof and are consequently flexed rearwardly in vmyingdegrees upon rotation of said rotor 19. The entire rotor 19 extendsbetween the end walls 12 of the chamber ll, and consequently the vanes23 define therebetween circumferentially spaced pockets 24 of varyingcapacity depending upon their position within the chamber 11.

As above indicated, rotors of the type immediately above described arerestricted in capacity because of the tendency of all of the vanes tocollapse inwardly in progression, much as though they were in actualengagement with each other (as in the case of dominoes or any objectsstanding on end in lined up relationship). In order to overcome thistendency and to greatly increase the capacity of pumps equipped withrotors having exible rubberlike vanes, the rotor 19 is formed so as toprovide certain circumferentially spaced pockets 24a which are ofgreater circumferential dimension than the remaining pockets 24 so as toaccommodate check valve-acting relatively rigid impeller elements 25.Impeller elements 25, as shown, are in the nature of relatively rigidrollers which extend between the end walls 12 which are mounted forlimited reciprocal movements upon rotation of the rotor 19 while inconstant contact with the cylindrical side wall 33. As shown, thepockets 24a are diametrically opposed and, to facilitate reciprocalmovements of the rollers 25, each thereof is provided with an axiallyextended radially outwardly opening channel 26 which is formed in thehub 20.

Preferably, and as shown, in order to prevent undue distortion and wearupon the rubber-like portion 22 of the perspective of some parts hub 29,the trailing edges of the channels zd have vult a t V canized theretoaxially extended radially projecting bearing flanges 27. Referringparticularly to FIG. 8, it will be seen that the bearing flanges 27 haveaxially spaced radially inwardly projecting legs 28 which are press fitin axially extended radially outwardly opening diametrically opposedslots 29 in the relatively rigid core element 21.

Our invention has been thoroughly tested and found to be completelysatisfactory for the accomplishment of the above objects, and while Ihave shown and described a preferred embodiment, I wish it to bespecifically under stood that the same is capable of modificationWithout departure from the spirit and scope of the appended claims.

What is claimed is:

1. In a fluid pump, a housing defining:

(a) a chamber having spaced parallel end walls and a cylindrical sidewall, and having circumferentially spaced inlet and outlet portscommunicating with said chamber,

(b) a shaft journalled for rotation in at least one of said end walls onan axis radially offset from the axis of said chamber,

(0) a rotor fast on said shaft within said chamber,

said rotor comprising:

(1) a hub concentric with said shaft and extending between said endwalls,

(2) a plurality of circumferentially spaced radially outwardlyprojecting flexible resilient vanelike impeller elements fast on saidhub,

(3) said impeller elements also extending between said end walls andhaving constant sweeping engagement with said cylindrical side wallduring rotation thereof and being flexed rearwardly in varying degreesduring such rotation, (4) said impeller elements defining a plurality ofcircumferentially spaced axially extended pockets of varying capacity,(d) one of said pockets defining a circumferentially and radiallyenlarged channel, and

(e) a relatively rigid impeller element mounted and guided in saidchannel for limited generally radial reciprocal movements with respectto said rotor and which during rotation of said rotor is insubstantially content engagement with said cylindrical side wall,

(7) the trailing side wall of said channel guiding said impeller elementin its generally radial reciprocal movements and positively retainingsaid impeller element within said channel during said rotation.

2. The structure defined in claim 1 in which the channel defined by saidone of said pockets extends between the end walls of said housing and inwhich said impeller element comprises an elongated roller receivable insaid channel.

3. The structure defined in claim 2 in which the radially outer portionof said hub and the vane-like impeller elements carried thereby areintegrally formed from rubber-like material and in which the trailingside wall of said channel is formed to provide a relatively rigidgenerally radially extended bearing flange for said roller.

4. The structure defined in claim 3 in which (a) said hub comprises agenerally cylindrical relatively rigid core element which isdiametrically enlarged with respect to said shaft,

(b) the peripheral portion of said core element being bonded to therubber-like portion of said hub, and

(c) in which said bearing flange is carried by and France Jan. 6, 1921Great Britain Feb. 28, 1939

1. IN A FLUID PUMP, A HOUSING DEFINING: (A) A CHAMBER HAVING SPACEDPARALLEL END WALLS AND A CYLINDRICAL SIDE WALL, AND HAVINGCIRCUMFERENTIALLY SPACED INLET AND OUTLET PORTS COMMUNICATING WITH SAIDCHAMBER, (B) A SHAFT JOURNALLED FOR ROTATION IN AT LEAST ONE OF SAID ENDWALL ON AN AXIS RADIALLY OFFSET FROM THE AXIS OF SAID CHAMBER, (C) AROTOR FAST ON SAID SHAFT WITHIN SAID CHAMBER, SAID ROTOR COMPRISING: (1)A HUB CONCENTRIC WITH SAID SHAFT AND EXTENDING BETWEEN SAID END WALLS,(2) A PLURALITY OF CIRCUMFERENTIALLY SPACED RADIALLY OUTWARDLYPROJECTING FLEXIBLE RESILIENT VANELIKE IMPELLER ELEMENTS FAST ON SAIDHUB, (3) SAID IMPELLER ELEMENTS ALSO EXTENDING BETWEEN SAID END WALLSAND HAVING CONSTANT SWEEPING ENEGAGEMENT WITH SAID CYLINDRICAL SIDE WALLDURING ROTATION THEREOF AND BEING FLEXED REARWARDLY IN VARYING DEGREESDURING SUCH ROTATION, (4) SAID IMPELLER ELEMENTS DEFINING A PLURALITY OFCIRCUMFERENTIALLY SPACED AXIALLY EXTENDED POCKETS OF VARYING CAPACITY,(D) ONE OF SAID POCKETS DEFINING A CIRCUMFERENTIALLY AND RADIALLYENLARGED CHANNEL, AND (E) A RELATIVELY RIGID IMPELLER ELEMENT MOUNTEDAND GUIDED IN SAID CHANNEL FRO LIMITED GENERALLY RADIAL RECIPROCALMOVEMENTS WITH RESPECT TO SAID ROTOR AND WHICH DURING ROTATION OF SAIDROTOR IS IN SUBSTANTIALLY CONTANT ENGAGEMENT WITH SAID CYLINDRICAL SIDEWALL, (F) THE TRAILING SIDE WALL OF SAID CHANNEL GUIDING SAID IMPELLERELEMENT IN ITS GENERALLY RADIAL RECIPROCAL MOVEMENTS AND POSITIVELYRETAINING SAID IMPELLER ELEMENT WITHN SAID CHANNEL DURING SAID ROTATION.